1. Field Of The Invention
The present invention relates to a system for scripting a text-to-speech-based multimedia presentation, and in particular, to a system in which a scripting file which includes text narration and multimedia commands is processed so as to separate the text from the commands, to enunciate the text narration, and to execute the multimedia commands.
2. Description Of The Related Art
Recently, the sophistication of computerized multimedia presentations has increased dramatically. Such presentations include audio programs, such as MIDI ("musical instrument digital interface") music and digitized speech, and video programs which may include bit map still video images and digitized motion video or animated features. The audio program and the video program are scheduled into a combined multimedia presentation.
Conventional scheduling systems for the audio program and the video program in multimedia presentations are time/event-based scheduling systems in which each program (or event is scheduled to begin and end at pre-designated times. Thus, for example, FIG. 7 shows a system for scheduling a multimedia presentation which includes MIDI music, digitized audio speech, still video, and digital motion video programs. Each aspect of the program is scheduled to begin and end at specifically noted times as set forth on the time line for each program. Thus, for example, the multimedia presentation begins with a still video presentation of a "credits" file, and a MIDI music presentation synthesized from an "intro" file. At thirty seconds into the multimedia presentation, digitized speech is scheduled to begin a voice-over sequence that plays out at the same time as the synthesized MIDI music. Meanwhile, the still video "credits" file is closed out and a digitized motion video sequence from an "introduction" file commences. Scheduling of the multimedia presentation continues in accordance with the illustrated time line.
The foregoing scheduling technique is not entirely satisfactory. To edit the schedule, for example, it is necessary to change all program parts to ensure that the remaining parts are properly coordinated with each other. Thus, extending the length of a digitized speech sequence, such as the "voice-over" file, requires changes in the MIDI time line and in the digital motion video time line to ensure that those programs remain properly coordinated with each other.
Moreover, each of the various programs (MIDI, digitized speech, still and motion video) requires large amounts of memory for storage. And, particularly in the case of digitized speech, it is necessary to re-record the entire speech sequence where an edit is required.